In this paper, in search of an approach for tuning the single-mol. magnet behaviors in lanthanide polynuclear compounds, two new dinuclear dysprosium compounds based on an 8-hydroxyquinoline Schiff base and two different β-diketonate ligands, [Dy2(hfac)4L2] (1) and [Dy2(tfac)4L2] (2) (HL = 2-[[(4-iodophenyl)imino]methyl]-8-hydroxyquinoline, hfac = hexafluoroacetylacetonate and tfac = trifluoroacetylacetonate), have been synthesized, structurally and magnetically characterized. The two Dy2 compounds have very similar structures, however, magnetic studies reveal that 1 and 2 showed different SMM behaviors with energy barriers of 15.70 K for 1 and 6.57 K for 2. The different SMM behaviors mainly result from the different coordination environments of the central DyIII ions in 1 and 2.